In extensive livestock farming, the “natural service” is the main reproductive method, consisting of putting in a same space (called “corral”) a large group of cows with a small number of bulls (e.g., 1 bull per 30 cows), for a period of time that may vary from one to several months (called “cattle breeding season”). The natural service involves essentially no technology, it follows a “black box” model where the inputs are cows, bulls, water and grass; and the outputs are pregnant cows. At most, a veterinarian is hired to perform specific actions at the beginning of the cattle breeding season (checking denture, general status of the animal, etc.). Ranchers more concerned with obtaining a good performance rely on an ultrasound scan of each cow at half-way of the breeding season, obtaining therefrom some information. Once the breeding season has finished, the pregnant cows are diagnosed: the natural service produces an average pregnancy-rate of 75% (with large variations among ranches from 30% to 98%). Even though obtaining rates near 100% depends on weather conditions, soil quality, among other factors that often are not well controlled, the average pregnancy-rate of the natural service is equally low. By obtaining process information, detecting problems in time and taking the respective corrective actions, there is no reason to believe that a substantial increase of the average pregnancy-rate is not possible.
There exist in the state of the art systems similar to the invention described in the present document, but whose purpose is the detection of estrus, generally for artificial insemination. Its application reaches narrow market segments but inclined to introduce technology in their processes, such as, for example, intensive livestock farming, feedlot, dairy or farms specialized in bovine reproduction.
An important subset of the above mentioned inventions is based on detecting the homosexual behavior that cows exhibit prior to or during the estrus cycle. By applying this principle, systems have been developed based on patches with paint placed on the back of the cow (see, for example, Herriot et al. U.S. Pat. No. 5,566,679). Painting patches break when a cow mounts another cow, which would indicate that the cow with the painted back is in heat, and the cow with the painted stomach is close to coming into heat. This is only possible in intensive livestock farming; in extensive livestock farming, installing a patch each time a bull mounting takes place is impractical, and automating detection of estrus is complicated and costly to implement, requiring human intervention to watch the painted animals. Furthermore, the cow estrus could happen at night (specially during hot weather in hot areas) and, as it only lasts a few hours, these systems may not detect it.
Bocquier (U.S. Pat. No. 7,992,521, Method and device for automatically detecting mating of animals, 2004) presents a device and method that allows the automatic detection of animal mounting. It can be seen simply as the modernization and automation of the classical “patch method” described above. It should be noted that this method/device at no time aims at detecting ejaculation. Indeed, the device is carried by a mounting animal that cannot ejaculate, referred to in general as male, but can be a castrated male, or a non-castrated male but unable to penetrate, or androgenized females. The Bocquier method is based on an electronic tag placed on the female and a device attached to the male by a belt, which has a detector of mounting attempts (which can be based on a pressure sensor on the stomach or a verticality sensor or a temperature sensor or a volumetric sensor) and an electronic tag reader placed in the female. Although having some points of contact with the present invention, both patents are fundamentally different regarding the problem they aim to solve. The present invention enhances the reproductive process based on the natural service (where necessarily the male has to ejaculate), while Bocquier et al. relates to the estrus detection (where there is no ejaculation). Moreover, there are several aspects that are not sufficiently addressed by Bocquier. In the first place, Bocquier proposes an anti-collision system for tag reading that works only to avoid male reading: it proposes essentially keeping a database with male IDs and excluding them if they were read. However, the tag reader carried by the male will read tags from any animal near the place of the mounting, and not necessarily the mounted female tag. This issue is important, since Bocquier's invention cannot identify, without a reasonable error margin, the mounted female. Secondly, Bocquier proposes a paternity checkup (col. 8 line 24) that cannot be implemented because if the system cannot detect ejaculation, there is no way to know who is the father. In third place, a reading of a tag (eventually located in the digestive tract of the female) involves radiating electromagnetic signals of great power that force the usage of large and heavy apparatus (since they require large batteries) and, therefore, harnesses or belts difficult to install, difficult to maintain and uncomfortable for the animal. Finally, Bocquier describes a process for the selection and classification of males that allows to conclude that his system would not work correctly with any male. This is a point that produces significant practical complications, since having to perform this process with all males would take too much time and would not be applicable to extensive livestock farming.
By using the same principle of detecting the homosexual behavior exhibited by cows prior and during estrus, systems and electronic devices, which are placed on the back of the cow and, by means of a switch, detect the mounting and report this information, have been developed, see, for example, Starzl et al. (U.S. Pat. No. 5,542,431, Heat detection for animals including Cows, 1996) or Claycomb et al. (U.S. Pat. No. 7,083,575, Electronic estrus detection device, 2006).
The other large subset of inventions found in the state of the art are based on detecting changes in the behavior of females. For example, when the cow is about to come into heat, their movement patterns change (particularly, they walk more) and they feed more. Therefore, by electronic devices installed on the legs or mouth, systems for detecting these changes with the purpose of determining if the cow is in heat have been proposed, see, for example Rodrian (U.S. Pat. No. 4,247,758, Animal Identification and estrus detections system, 1981) or Voronin et al. (U.S. Pat. No. 7,878,149, Method and device for detecting estrus, 2011).
All solutions mentioned so far have the cow as a center, i.e., they are characterized by placing an active (requiring its own power source) and complex (intelligent, with sensors and means of communication, with a large size, complicated to install) device in the cow, thereby not being applicable in extensive livestock farming (where the ratio between the number of cows and the number of bulls is very high, and the production process needs to be developed with no or little human intervention).
Lowe (U.S. Pat. No. 8,066,179, Livestock Breeding and Management System, 2011) presents a method and system for managing livestock breeding that does not have the cow as the center. The system/method consists of each female having a RFID tag and each male carrying a device (referred to as “monitor” by Lowe) capable of detecting mounting (based on the position of the body of the male) and reading the female RFID tag. This allows to generate the following information: ID of the mounted female, ID of the mounting male, date and time of the mounting. This activity information is entered into a management system where information is generated for the management of the reproductive process. According to Lowe, the management information could be: date of conception, indication of whether the female is pregnant or not, estimated date of birth, conception success rate for male, fertility rate for female, ease impregnation rate of female and offspring family information.
Even though Lowe has several points of contact with the present invention, it has an essential difference in the way the efficacy of a mounting is determined, i.e., if there was ejaculation. Lowe determines ejaculation based on the time the mounting lasts (col. 6 line 50; col 7 line 35; col 9 line 56), whereas our invention has a specific system for detecting ejaculation. At this point, it is important to note that ejaculation by the male does not depend on the duration of the mounting. Short duration mountings can involve ejaculation, while long duration mountings may not involve ejaculation. Tag reading as used by Lowe (col. 6 line 55; col 6 line 63) has a significant error margin, adding more uncertainty to the determination of the efficacy of the mounting, since it could read the tag of any female within the reader's range of action and which is not being mounted. There are other aspects that are not sufficiently addressed by Lowe. In the first place, the tag reader carried by the male will read tags from any animal (including the same tag of the male) near the place of the mounting, and not necessarily the mounted cow tag. This issue is important, since Lowe's invention cannot identify, without a reasonable error margin, the mounted female. Secondly, the attachment is not solved correctly. The use of a collar, muzzle or harness (col. 6 line 10) is proposed. This type of solution is difficult to install, difficult to maintain and uncomfortable for the animal. In third place, the magnetic field configuration/modification of parameters of the RFID tag reader for attempting to enhance the detection of the mounting, made in a generic manner (col. 7 line 3) or manually for each monitor (col. 7 line 13) is impractical and its results are unreliable.
As will be shown in the following section, our invention discloses a system seeking to solve the same problem as Lowe, and it succeeds in adequately solving, with inventive step: the identification of the mounted female and determining whether the mounting was effective or not. The shortcomings shown by Bocquier and Lowe regarding the above mentioned points, question whether these inventions can truly solve the problems they claim to solve. For example, Lowe's system, by not being able to adequately identify the mounted female and/or determining whether the mounting was effective or not, would not provide the information he says his system will provide (date of conception, indication whether the female is pregnant or not, estimated date of birth, conception success rate for male, fertility rate for female, ease impregnation rate of female and offspring family information).